Step-by-step explanation:

While subtracting , the sign of each term of second expression changes & remove the parentheses.
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Combine like terms. Like terms are those which have the same base. Only coefficients of like terms can be added or subtracted.
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In standard from , the expression should be written in such a way that the power of variables goes from highest to lowest.

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Answer:
4 + 3x
Step-by-step explanation:
Let the number = x
Product of three and a number = 3*x = 3x
Sum of four and 3x = 4 + 3x
Answer:
9
Step-by-step explanation:
Special right triangle
this is a 45, 45, 90 triangle
Meaning that whatever the hypotenuse is
that it will be the same for x
Step-by-step explanation:
Evelyn: Y=89x + 19
Brenda: Y=87x + 21
Punch in numbers for X until you get the same for both. Remember that X is hours and Y is total. the numbers with no letters is the fixed booking amount. cheers. Good luck :)